\usepackage[active,tightpage]{preview}
\renewcommand{\PreviewBorder}{1cm}
\newcommand{\Newpage}{\end{preview}\begin{preview}}

\usepackage{geometry}
\geometry{
  textwidth = 74em
}

\usepackage[dvipsnames]{xcolor}

\usepackage{tikz}
% \usepackage{pgf}
% \usetikzlibrary{trees} % this is to allow the fork right path
\usepackage{tikz-qtree}
% \usepackage{tikz-qtree-compat}
% \usepackage{forest}

\usetikzlibrary{positioning}

% \usepackage[scheme=plain]{ctex}
\usepackage[UTF8]{ctex}

\def\tikzname{Ti\emph{k}Z}
\def\pgfname{\textsc{pgf}}

% \usepackage{bold-extra}
\usepackage{setspace}
\setstretch{1.0}